I made this invention after puzzling for five years over how to build a better outdoor, covert, pan, tilt, and zoom camera with mechanical, not digital, pan and tilt, and optical, not digital, zoom. I was aware of the prior art, single-axis, forward-pivot movement shown in FIG. 10, and the larger, two axis version, both for use primarily with a pinhole lens that is specially built for the purpose. I was unhappy with its need for a pinhole lens, not to mention one that is specially built for a particular forward pivot movement, use primarily indoors due to the need for a pinhole opening, its large gears and complex mechanism, the few choices of lenses, all of which were expensive, the lack of day/night capability, which requires a CdS photo sensor and a motorized IR-cut filter, and the tiny aperture and thus poor low light capability of a pinhole lens. I was aware of common pan-tilt mechanisms with their need for a large window and a single point of camera suspension for each axis. I was also aware of cameras with digital pan, tilt and zoom, which have orders of magnitude less resolution of a region of interest than a camera with mechanical pan and tilt, and optical zoom, simply because they can't be pointed mechanically under remote control in the direction of interest.
Outdoor cameras must be weatherproof. They require a means for the camera to view the world while keeping moisture and dirt out of the camera. Exposed domes cannot be used in covert applications because they scream, “camera here,” defeating the purpose of having a camera, hence flat windows that are several inches across and coplanar with a wall of a rectangular enclosure are generally used. A tiny, e.g., pinhole aperture, along with a pinhole lens, is often used indoors but is not suitable outdoors because it allows the elements to get into the camera, and a small hole can become clogged easily by dirt and insects. A small flat window can be used in place of a pinhole, but windows cannot be arbitrarily small due to fabrication and optical issues, and the bigger the window, the less benefit is obtained from a pinhole lens. Using a larger lens, at the expense of a larger window, offers better performance and far more lens choices.
Outdoor cameras should also have remotely controlled, motorized, pan, tilt and zoom so they can be aimed from a distance. If the camera is used in a vehicle, or is to be moved from place to place for temporary applications, as is common in covet work, its pan and tilt movement needs to be rugged. However, most pan and tilt movements have 360-degree horizontal movement and 180-degree vertical movement, and only a single point of suspension for each camera axis and do not handle rough movement well.